Device for cementing wells



Sept. 6,1927.

A. BQYNTON DEVICE Foa CEMENTING wELLs Filed Dec. 2l, 1925 ATTORNEYS Patented Sept. 6, 1927.

UNITED STATES PrllTEiaT4 OFFICE.

A ALEXANDER BoYN'roN, or sAN'rAN'roNIo, rams.

AIDIEVIICE FOB CEMENTING Application led December 21, 1925. Serial No. 76,839.

in cementing two-string wells although itv may be slightly modified and converted to carry out the cementation of one-string wells when desired. Y

One of the principal objects of the invention resides in the provision of a device wherein the discharge of the cement is con trolled by a float valve -assembly which coacts with a seat arrangement in the Well casing and wherein the loat valve assembl is so constructed and organized as to a ord double assurance of the proper engagement of its valvevmeans with the valve seat arrangement whereby to insure proper action at the proper time.

A further object resides in the provision of a novel form of cement discharge means which comes into action when the cement cannot be discharged below the shoe at the bottom of the cementing device and which will not deteriorate in time and be liable to break through, the cement discharge means being positive in artion. A still further object is to provide an arrangement of back pressure valves which assures effective action in this respect under all circumstances.

Another object is to provide an improved means for locking the casing shoe, couplings and connections against backing off when the signal valve assembly and back pressure valves are being drilled out.

Other objects and advantages reside in certain novel features of the construction, arrangement and combination of parts which lwill be hereinafter more fully described and particularly pointed out in the appended claims, reference being had to the accompanying drawings forming a part of this specilication, and in which:

Figure'l is a view in transverse vertical section showing a cementing device embodying the present invention, parts being shown in elevation for the sakey of illustration,

Figure 2 is a view in elevation showing theudevice adapted for use with one-string we s,

Figure 3 is a detail view partly in section 16.

tion and partly in edge elevation showin one of the cement discharge valves employe in both embodiments of the invention,

Figure 4 is a view thereof in front elevation,

Figure 5 is a sectional view on the line 5-5 of Figure 1, and

Figure 6 is a detail .perspective -view of one of the locking keys employed.

Referring to the drawings it will be seen that the cementing device is made up of .a number of hollow cylindrical sections 1 and 2 coupled together by means of a coupling sleeve 3 which is locked to the sections by means yof keys 4 driven in between the coupling sleeve and the sections. The keys 4 are shown in detail in Figure 6 and are shaped to become imbedded in the casing as the keys are driven in place, the outside portions of the keys being received in slots in the coupling. The upper end of the secltionvl is provided with a coupling 5 which y.is locked thereto by other keys 4 and the coupling 5 affords means 'whereby the oementing device may be connected to the lower end of the well'casing. v

In the form of the invention shown in Figure 1 a set shoe 64 is threadedly connected to the lower end of the section 2, as indicated at 7, and is locked to the section by means of a number of keys 4 which are identical with the keys 4 except that they are longer.

Between the sections 1 and 2 the flange 8 of a valve seat 9 is clamped and such flange is held in position by means of lock screws 10 co-actingwith the coupling 3 and with the flange, asshown in Fi re 1. The valve seat 9 has a conoidal portionll and an oppositely disposed conoidal portion 12, the conoidal portions 11 and 12 being connected by a short cylindrical portion 13 and in the conoidal. ortion 12 a valve seat 15 i`s provided. Tllie flange 8 is connected with the lower end of the conoidal portion 11 by means of a short cylindrical connecting, por- A spider 17 is integral with or suitably connected to the flange 8 and to the short cylindrical portion 16 and carries a back pressure valve, designated generally at 18. The present Finvention not only provides the back pressure valve 18 but also provides a second back pressure valve 20 ally at 25, is provided and includes a stem 26 having a main valve 27 integral with or suitabl secured to its lower end, the valve 27 pre erably being in the form of a cup de signed to co-act with the seat 15. An auxiliary movable valve 28 is provided and also takes the form of a cup or hollow semisphere. The valve 28 has a flanged opening 29 at its lower central portion which slidably" receives the stem 25. A. light coil sprin 30 is mounted on the stem and is tension to displace the valve 28 upwardly on the stem, t e upper end of the spring engaging the valve 28 and the lower end engaging the fixed valve 27. A nut 31 revents the valve 28 from be' displace from jthe stem. The valve 28 1s desi ed to co-act with a valve seat 32 fastenello the coupling 5 by means of lock screws 33 as well as by virtue of a threaded connection. The distance between the valves 27 and 28, as normally disposed, is greater than the distance between the seats 32 and 15. The specific gravity of the entire valve assembly is greater than the 30 mud fluid and less than that of liquid cement but the specific gravity of the main valve 27 1s slightly greater than the cement while the specnic gravity of the auxiliary valve 28 is considerably less'than that of the cement.

y The section 2 is. provided with cement discharge openings 35 which have their outer portions or walls countersunk to provide valve seats 36. Metal valves 37 in the form of half spheres co-act with the valve seats 36 and these metal valves 37 are spot welded or otherwise suitably secured to blade sprmg-like carriers 38, the ends of which have slots39 co-acting with headed 'pins 40 fastened tothe section 2. The spring carmers 38 are tensioned to holdthe valves a ainst their seats 36 but under the influence o a certain predetermined degree of'pressure exerted against the valves and the carners these sprlng carriers may be flexed outwardly to permit discharge through the openings 35. Outward llexure is permitted by virtue o'f the provision of the slots 39. In operation with this form of the inven- `tion the cement is placed in the well and the valve assembly 25 1s placed thereon and the mud fluid is t en pumped down onto the cement so that the cement valve assembl v and mud fluid Vtravel down t o h the we cas-l ing until all of the cement -passed out under the set shoe or out through the valve controlled openings 35 as the case may be.

-It sometimes happens that the casing sticks or in the well in such manner as to prevent the cement from being forced out under the set shoe. This does not impair the eicacy of applicants cementing process and device2 for under such circumstances the cement 1s discharged through Vthe valve controlled openin 35.

When .all of the cement has assed through the valve seat 15, the va ve 27 strikes this seat and unless held unseated by an obstructionprevents 'further downflow of fluid or liquid and causes the pump to stall, thereby advising the operator that the cementation has been completed. Should the valve 27 fail to seat for any reason the down iow of liquid which follows the same will shift the movable valve 28 downwardly against the tension of its spring 30 to seat the valve 28 againstthe seat 32 and effect a seal at such point which will cause the pump to stall in the same manner as if the valve 27 had properly engaged its seat 15.

By providing two back pressure valves, in the event of failure of one valve lto seat the other will seat whereby double assurance in this respect is had.

This device may be readily converted for use with one string wells omitting the Set shoes 6 and the back pressure valve 20 and replacing these parts with a couplinlg 40 and brass plate barrier 41 as shown 1n igure 2. In one string wells the liner 42 is suspended below the well casing 4311s shown in the drawing and it will be desirable to provide suitable formation packers, such as indicated at 44, below the cementing device and above the liner.

The valve seats are made of soft brass or l. A cemeuting device compri I 'a discharge section having an opening lea 'ng out y through its lower end through which the cement 1s to be discharged and also having a plurality of spaced back pressure valves above the opening and cement discharge openings between the back pressure valves.

2.A cementing device comprisin a discharge section having an'opening lea 'ng out through its lower end through which the cement 1s to be discharged and also having a plurality of spaced back pressure valves above the opening, said discharge section also having cement discharging openings betweernthe back pressure valves, and s ring closed valves controlling said last-mentioned cement dischar openings.

3. A cementmg device for use with well casings having a plurality of spaced seats and comprising a iioat valve aembly including a main valve comparable with one main valve, a movable llow cntrolle'd valve co-operable with the other seat, a coil spring between the valves, the valves being normally spaced by the cil spring at a dis of the seats, a stem connected with the said leading `out through itsA lower en tance greater than the distance between the seats, the entire valve assembly being lighter than the cement though heavier than the' mud fluid, the fixed valve being-slightly heavier than the cement and the movable valve being lighter than the cement.

' 4. `A cementing device for wells comprisa dischargesection having an oenin through which the cement may be dis- 10 charged, a back ressure valve above said. opemng, said disc arge section also Vhavin peripheral discharge openings above sai back pressure valve, and spring closed metal valves yco-operable with said peripheral dis- 15 charge opening.

' ALEXANDER BOYN'ror. 

